1. Field of the Invention
The present invention relates to a liquid crystal display.
2. Description of the Related Art
A conventional liquid crystal display portrays images by controlling the light transmittance of liquid crystal using an electric field. To this end, the liquid crystal display includes a liquid crystal panel in which liquid crystal elements are arranged in a matrix form and a driving circuit for driving the liquid crystal display panel. In the liquid crystal display 100 as illustrated in FIG. 1, a liquid crystal display panel 140, in which data lines Data [1] to Data [m] coupled to a data driver 120 and gate lines Gate [1] to Gate [n] coupled to a gate driver 110 are crossed, is provided with thin film transistors (TFTs) for driving liquid crystal elements CLC at the crossed portions. The liquid crystal display panel is further provided with storage capacitors Cst for maintaining the voltage of the liquid crystal element CLC. The liquid crystal element CLC controls the amount of light transmitted or shields light by changing the arrangement of liquid crystal molecules with an electric field in a liquid crystal layer therein. The electric field is generated when data voltage is applied to a pixel electrode 141 from the data driver 120 and common voltage Vcom is applied from a common voltage supplier 130.
In the liquid crystal display 100, the common voltage line is formed in a short structure within the liquid crystal display panel. When the common voltage is applied to a common electrode 142 and the gate voltage is input to apply the data voltage to the pixel electrode 141, the storage capacitor Cst, coupled between the common electrode 142 and the pixel electrode 141, charges an amount of charge corresponding to the voltage difference therebetween. However, while the gate voltage moves from the left-most pixel to the right-most pixel, a delay error occurs so that an error between the data voltage value applied to the pixel electrode at a left end and the data voltage value applied to the pixel electrode at a right end occurs due to the delay. In order to minimize the delay error, the common voltage is applied to both ends of the liquid crystal display by shorting both ends of the common voltage line. Presently, the delay error does not occur in the first pixel or the last pixel. However, the delay error occurs in the pixel coupled to a central column, that is, a data line Data [m/2]. Even though the common voltage is applied at both ends of the common voltage line, each pixel becomes more asymmetrical in the amount of charge the closer the pixel is to the central column of the liquid crystal display. An afterimage occurs due to asymmetrical amounts of charge when a pattern changes, and the remaining voltage occurs due to the unnecessary amount of charge.